Nudi Pixel: Nudibranchs and Sea Slugs Identification with Photographs

Comment from Nathalie Yonow: This looks like Phyllidiella zeylanica with black rings around the mantle and a faintly darker band centrally. The large black rhinophores help also. I would have liked to see the front end of the animal - Phyllidiella zeylanica has the parallel black lines quite squared off in front.